To create a transfer function from an incoming signal processed by an analog-to-digital converter (ADC), one must apply a Fast Fourier Transform (FFT) to analyze the signal's frequency components. The process involves stepping through a range of frequencies using a variable frequency signal source and recording the ADC output to determine the input-output relationship. For voice analysis, the signal is captured through a microphone, and the resulting data can be used to derive the transfer function mathematically. It's important to understand that the transfer function can be represented in the z-domain, where the relationship between input and output sequences is established. Ultimately, the goal is to compute the discrete Fourier transform of the sampled signal to visualize its frequency spectrum.
